> I get "Internal error #300" and "Mac OS error -23" pointing to a
>funkyness on the part of the TCP/IP stack / driver / panel / thingy,
>as far as I can see from looking up endless pages of error codes.
>And I've made all the settings recommended... also, the cable is
>known good and works perfectly when drug back into the office and
>hooked up to this laptop upon which I type.

Have you run something like DiskWarrior on the HD? That would be my
first recommendation, the second would be to reload the OS, it sounds
like you might have some sort of corruption. The Mac filesystem is a
lot less robust than I'd like. You should be able to simply
reinstall the OS over your existing setup, and hopefully not have to
do much else.